Integrated solar thermal system

ABSTRACT

An integrated solar thermal system for a building roof is provided. The system utilizes a plurality of fin pipes to collect solar energy as heat, and to transfer this heat to a working fluid conveyed in a parallel flow through the fin pipes. The heated working fluid is then used for productive energy conversion.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates generally to solar energy collecting devices. More particularly the present invention relates to a roof panel for a building having an integrated solar thermal system.

Description of Related Art

The need exists to optimize energy efficiency in building heating, cooling, and powering systems. This is particularly important in light of increasing energy costs and global warming concerns. The more that a building can take advantage of energy efficiency and clean power, the better. One example of clean power that there is an abundance of is solar radiation energy. This solar energy continually beats down on upward facing surfaces, such as roofs. Attempts have been made in the past to harness this energy through, for example, solar panels, solar collecting installations, and building add-ons to absorb heat and other energy. However, these suffer from numerous shortcomings and are typically not cost effective.

Therefore, what is needed is a simple, cost effective and efficient system that can absorb solar energy, covert it to heat, and extract this heat energy for useful purposes.

SUMMARY OF THE INVENTION

The subject matter of this application may involve, in some cases, interrelated products, alternative solutions to a particular problem, and/or a plurality of different uses of a single system or article.

In one aspect, a roof for a building is provided. The roof comprises a solar heat absorbing fin pipe assembly. This assembly utilizes a plurality of elongate fin pipes attached to each other along lengthwise edges. However, in other embodiments, the elongate fin pipes may be spaced apart in a parallel arrangement under a metal roof. Each fin pipe may have a pipe defining a flow channel through its interior, and a fin or fins extending along a top of the pipe. The fin/fins form a top platform to absorb incoming radiant energy such as solar energy. The pipe extends downward from a bottom of the fin(s). These fins are typically integrally formed with the pipe and together form a top face configured to receive a solar radiation. A quantity of piping is attached to the fin pipe assembly. This piping is configured to connect a fluid flow to the inlet and outlet side of the fin pipe assembly to provide parallel fluid flow through the assembly from a first cold end to a second hot end. The piping may comprise an inlet pipe leading to an inlet header which splits into a plurality of parallel inlet flows. Each inlet flow connects to one of the flow channels of the plurality of fin pipes at a first cold end. Outlet flows exit the plurality of flow channels at the second hot end and join together at an outlet header. An outlet pipe connects to the header and conveys fluid out of the system for energy conversion to productive uses. This fin pipe assembly is positioned such that the two fins of each of the plurality of fin pipes forms a top outer surface of the roof. In a particular embodiment, a single inlet flow may be split at a second hot end and reversed back in an opposite direction as two outlet flows, passing again back over the heated fin(s). These two outlet flows may then rejoin at the outlet header at the same side as the initial inlet flow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 provides a partial cross sectional view of an embodiment of the present invention.

FIG. 2 provides another partial cross sectional view of an embodiment of the present invention

FIG. 3 provides a perspective view of another embodiment of the present invention.

FIG. 4 provides a side cross sectional view of yet another embodiment of the present invention.

FIG. 5 provides a view of an embodiment of the present invention in use on a roof of a building.

FIG. 6 provides yet another view of an embodiment of a multi-panel array.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of presently preferred embodiments of the invention and does not represent the only forms in which the present invention may be constructed and/or utilized. The description sets forth the functions and the sequence of steps for constructing and operating the invention in connection with the illustrated embodiments.

Generally, the present invention concerns a roof-integrated solar thermal system. The system operates generally by passing fluid in parallel flow through one or a plurality of panels using fin pipes, with the fins being sun facing. Fluid passing through the fin pipe assembly is heated by sunlight, and energy is extracted from this heated fluid for useful purposes including home heating, electricity generation, and the like. In a preferred embodiment, the panels and roof elements are pre-fabricated, allowing for simple, modular, and rapid installation. As such, the present invention may be installed as a single unit serving the dual purpose of creating a roof covering that also operates as a solar energy collector.

In one embodiment, the fin or fins of the fin pipe may operate as the material of the roof itself. In another embodiment, a metal (or other roof material) panel or layer may be directly connected to the fin pipe surface. In one embodiment, this roofing material may be connected to the fin pipe surface using a heat conducing tape or adhesive to provide enhanced heat conductivity.

In one embodiment, the present invention may utilize parallel flow for a plurality of fin pipe flow channels. As such, cold side fluid enters each of the fin pipe flow channels at a first end after being split from an inlet flow header. After passing through the length of the fin pipe flow channel, being warmed by heat from the sun, the fluid exits from each channel at a second hot end and rejoins at a header. This provides superior heat absorption compared to prior art serpentine flow patterns, providing for more even and efficient heat absorption by the working fluid.

In further embodiments, insulation may be installed to a back of the fin pipe assembly. This insulation is preferably assembled as part of the pre-fabricated piece but optionally may be installed after roof installation. The insulation may maximize heat transfer from the fin pipe to the fluid to be heated, and also may serve as building roof insulation. Typically rigid foam board insulation is used, however any insulation may be used without straying from the scope of the present invention.

In some embodiments, multiple pieces of the roof assembly may be attached together to form a weather tight seal. Options for attaching the pieces together may include, but are not limited to mechanical connections such as bolts, rivets, tongue and groove fitting, and/or adherent connections such as sealants, adhesives, caulks, and the like. In other embodiments fins may overlap on adjacent panels with one fin positioned above another to form an overlapping sealed connection.

The materials of the present invention may be selected to be rigid and durable enough for roof usage, that also are good conductors of heat. Typical materials may include metals, especially conductive metals such as aluminum, copper, and the like. However, it is to be understood that any material may be used without straying from the scope of the present invention. In many embodiments, the metal selected may be an unglazed metal panel allowing for direct exposure to the metal.

The fluid used by the present invention to absorb the heat from the fin pipes, which may be referred to herein as “working fluid,” may be any fluid capable of being pumped through the flow channels to absorb heat. Typically this fluid may be water or a water based solution or mixture. However, fluids including glycol solutions, alcohols, and the like may be used. As noted, other fluids may also be used, so long as they may be flowed through the requisite channels, piping, and the like, to absorb heat.

Turning now to FIG. 1, a partial cutaway view of a panel of the present invention is provided. A bottom of the panel is in view. In this view, a panel is shown formed as a fin pipe 10. Fin pipe 10 comprises fins 11, as well as a pipe 12 which defines flow channel 13. Fins 11 extend away from pipe 12 on both sides. As noted briefly above, fin pipe 10 is formed of a conductive material to conduct heat absorbed from sunlight into a fluid flowing through flow channel 13. Generally, pipe 12 and fins 11 are integrally formed, such as molded, extruded, or the like, in a single piece. Further, pipe 12 and fins 11 are also formed of the same material, in most embodiments. While FIG. 1 provides a view of a fairly short fin pipe 10 panel, it should be understood that the panels typically extend along all or most (that is, greater than 50%) of a length or width of the roof. As such, typical fin pipe 10 panels are, in practice, often elongate rectangular shapes.

FIG. 2 shows another embodiment of the panel of the present invention from a top view. In this view, fins 11 can be seen to be flat and continuous across the top face that is designed to be the sun-facing surface or in the sun-facing direction. In most embodiments, this sun facing surface will be an unglazed metal. As in FIG. 1, at an approximate widthwise center (though not necessarily so) the pipe 12 defines flow channel 13.

FIG. 3 provides a view of an embodiment of an underside of multiple panels of the present invention formed as a fin pipe assembly and the corresponding piping. In this view, three panels 10 are connected together along a lengthwise edge. This connection may be mechanical (such as tongue and groove, etc.), adhesive, overlapping, or a combination. Fins 11 extend outwardly from the pipes 12. A fluid piping is connected to inlet and outlet sides of the fin pipe panel assembly is shown. In this embodiment, a roof panel 36, such as a metal roof sheet, is attached to the top surface of fins 11. However, it should be understood that this is not required for all embodiments. In some cases, a lining (not shown) may extend into the flow channel, this lining may be a continuation of the inlet/outlet piping, or may be a separate material or structure. The term pipe and piping is used herein to refer to not only pipes, but also tubes, and any other structure capable of substantially containing a flowing fluid. Inlet piping 33 delivers relatively cold fluid to the inlet of the fin pipe assembly at a first cold end. Fluid flow 32 passes through the fin pipe to an opposite second hot end. At this opposite end, the fluid flow 32 is split and redirected at splitter 34. This fluid flow 32 is again passed through the fin pipe to the first end having been heated by the piping on two passes. Fluid flow 32 is combined in a header and exits the system via outlet flow 31. In some embodiments, flow channels for flow before and after splitter 34 may be the same size. In such an embodiment, flow rate after the splitter 34 will have a lower velocity than before the splitter. This may be advantageous by allowing the post-splitter flow to have a longer residence time in the chamber to be heated. In some cases, these inlet flows 32 may be pipes or tubes having a threaded end that is connected to a threaded connector of the channel 13 of pipe 12. When sunlight is applied to the array (on the opposite side from shown), it will heat up, this heat is transferred to each fluid flow 32. Upon exiting the opposite side of the fin pipe assembly at the outlet flow 31, fluid will be hotter than when it entered and exits the system to be used for productive purposes. Once the heat of outlet flow 31 has cooled, it may be recycled back to inlet flow 33. It should be understood that pumps (not shown) and/or other fluid conveying means may be used to move fluid throughout the system. Further, while this view is shown using three separate fin pipes, a single fin pipe may be provided with multiple pipes 12 defining multiple chambers 13 without straying from the scope of this invention.

FIG. 4 provides a side view of the fin pipe assembly of FIG. 3. In this view, insulation 35 can be seen covering a bottom of the fin pipes 10 and fluid flow channels. This insulation is configured to maximize heat transfer to the fluid 32 and minimize heat loss elsewhere. As shown, fins 11 are connected to adjacent pipes along lengthwise edges.

FIG. 5 provides a view of an embodiment of the fin pipe assembly in position as a roof of a building. Fin pipe panels 10 are arranged to cover the roof of the building. Each panel has at least one flow channel 13. As sunlight and other solar radiation (Infrared/visible/UV, etc.) 51 contacts the panels 10, it is converted to heat energy. This heat energy is transferred to fluid passed through channels 13. The outlet flow 33 is conveyed to a converter 52 which productively uses the heated fluid outlet flow 31. Once used, cooled fluid 53 exits the converter 52. This outlet cooled fluid 53 may be recycled back to the inlet flow (33) in a closed system embodiment. Examples of converters 52 that make productive use of hot outlet fluid 31 may include, but are not limited to home heaters, radiators, electric generators, and the like.

FIG. 6 provides another view of a fin pipe assembly having multiple fin pipes and inlet and outlet headers. Similar to FIG. 3, an inlet flow 33 provides cold fluid to a first end of the panel. Cold fluid is delivered via header 62, which provides multiple inlet fluid flows 32 to the different panels. Each fluid flow 32 leaves inlet header 62, travels to a second opposite end, splits at splitter 34, reversing direction and travelling back to the first end. At the first end, flows 32 join together in heard pipe 61 and exit the system as outlet flow 31. The fin tube assembly shown preferably is prefabricated, and during installation, only inlet and outlet headers 62, 61, need be installed.

While several variations of the present invention have been illustrated by way of example in preferred or particular embodiments, it is apparent that further embodiments could be developed within the spirit and scope of the present invention, or the inventive concept thereof. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present invention, and are inclusive, but not limited to the following appended claims as set forth. 

What is claimed is:
 1. A solar heat absorbing fin pipe assembly for use as a roof comprising: a plurality of fin pipes, each fin pipe comprising a pipe defining a flow channel, and two fins extending away from a top of the pipe such that the pipe extends downward from the fins, the fins integrally formed with the pipe and together forming a top face configured to receive a solar radiation, wherein the two fins are formed of an unglazed metal; wherein each fin pipe is arranged to be parallel to an adjacent fin pipe; and a quantity of piping attached to the fin pipe assembly, the piping comprising an inlet pipe, an inlet header splitting into a plurality of parallel inlet flows, each inlet flow connecting to one of the flow channels of the plurality of fin pipes, an outlet header connecting outlet flows from each of the flow channels, and an outlet piping.
 2. The solar heat absorbing fin pipe assembly for attachment to a roof of claim 1 wherein a first end of the flow channel of each of the plurality of fin pipes comprises a first threaded connector, and wherein a second opposite end of the flow channel comprises a second threaded connector, and comprising a first quantity of piping of the inlet flow connected to the first threaded connector, and a second quantity of piping connecting to the second threaded connector and to the outlet header.
 3. The solar heat absorbing fin pipe assembly for attachment to a roof of claim 1 further comprising a pipe liner within each flow channel of the plurality of fin pipes.
 4. The solar heat absorbing fin pipe assembly for attachment to a roof of claim 1 wherein each fin pipe is formed of a unitary unglazed aluminum.
 5. The solar heat absorbing fin pipe assembly for attachment to a roof of claim 1 wherein each fin pipe is formed of a single material.
 6. The solar heat absorbing fin pipe assembly of claim 1 further comprising a splitter, the splitter separating the flow of the flow channel at a second end of the flow channel opposite a first inlet end, the splitter further directing the separated flow through two second channels formed by two second pipes connected to the two fins and parallel with the channel, wherein the outlet header and inlet header are both positioned by the first end of the flow channel and second flow channels.
 7. The solar heat absorbing fin pipe assembly for attachment to a roof of claim 1 further comprising a quantity of insulation covering a bottom face of the fin pipe.
 8. A roof comprising: a solar heat absorbing fin pipe assembly comprising: a plurality of fin pipes, each fin pipe comprising a pipe defining a flow channel, and two fins extending away from a top of the pipe such that the pipe extends downward from the fins, the fins integrally formed with the pipe and together forming a top face configured to receive a solar radiation, wherein the two fins are formed of an unglazed metal; wherein each fin pipe is arranged to be parallel to an adjacent fin pipe; a quantity of piping attached to the fin pipe assembly, the piping comprising an inlet pipe, an inlet header splitting into a plurality of parallel inlet flows, each inlet flow connecting to one of the flow channels of the plurality of fin pipes, an outlet header connecting outlet flows from each of the flow channels, and an outlet piping; a quantity of insulation attached to a bottom of the assembly covering a portion of the two fins and the pipe of each of the plurality of fin pipes; and wherein the fin pipe assembly is positioned such that the two fins of each of the plurality of fin pipes forms a top outer surface of the roof.
 9. The roof of claim 8 further comprising a metal roof panel attached to the two fins of each of the plurality of fin pipes.
 10. The roof of claim 9 further comprising a heat conducing adhesive attaching the metal roof panel to the two fins of each of the plurality of fin pipes.
 11. The roof of claim 8 wherein a first end of the flow channel of each of the plurality of fin pipes comprises a first threaded connector, and wherein a second opposite end of the flow channel comprises a second threaded connector, and comprising a first quantity of piping of the inlet flow connected to the first threaded connector, and a second quantity of piping connecting to the second threaded connector and to the outlet header.
 12. The roof of claim 8 wherein each fin pipe is attached to a lengthwise edge of an adjacent fin pipe forming a waterproof connection.
 13. The roof of claim 8 further comprising a splitter, the splitter separating the flow of the flow channel at a second end of the flow channel opposite a first inlet end, the splitter further directing the separated flow through two second channels formed by two second pipes connected to the two fins and parallel with the channel, wherein the outlet header and inlet header are both positioned by the first end of the flow channel and second flow channels.
 14. The roof of claim 1 wherein the outlet piping is connected to an energy converter configured to extract a heat from a fluid from the outlet piping.
 15. A building having a roof, the roof comprising: a solar heat absorbing fin pipe assembly comprising: a plurality of fin pipes, each fin pipe comprising a pipe defining a flow channel, and two fins extending away from a top of the pipe such that the pipe extends downward from the fins, the fins integrally formed with the pipe and together forming a top face configured to receive a solar radiation, wherein the two fins are formed of an unglazed metal; wherein each fin pipe is attached to a lengthwise edge of an adjacent fin pipe forming a waterproof connection; a quantity of piping attached to the fin pipe assembly, the piping comprising an inlet pipe, an inlet header splitting into a plurality of parallel inlet flows, each inlet flow connecting to one of the flow channels of the plurality of fin pipes, an outlet header connecting outlet flows from each of the flow channels, and an outlet piping; a quantity of insulation attached to a bottom of the assembly covering a portion of the two fins and the pipe of each of the plurality of fin pipes; and wherein the fin pipe assembly is positioned such that the two fins of each of the plurality of fin pipes forms a top surface of the roof; wherein the roof is positioned on a top of the building and configured to protect the building top from an external environment; and wherein the outlet piping is connected to an energy converter configured to extract a heat from a fluid from the outlet piping.
 16. The building of claim 15 wherein the energy converter is a heating radiator positioned on an interior of the building.
 17. The building of claim 15 wherein the energy converter is an electric generator.
 18. The roof of claim 15 further comprising a metal roof panel attached to the two fins of each of the plurality of fin pipes.
 19. The roof of claim 18 further comprising a heat conducing adhesive attaching the metal roof panel to the two fins of each of the plurality of fin pipes.
 20. The roof of claim 15 wherein the two fins of each of the plurality of fin pipes forms an outer weather-exposed surface of the roof. 